1. Field of Invention
This invention relates to a system and method for reducing the concentration of one or more metal species from a waste stream and, in particular, to a system and apparatus for removing one or more metal species from chemical mechanical planarization waste slurry streams.
2. Discussion of Related Art
Techniques can be employed for reducing the concentration of the one or more target species from a stream. For example, Medford et al., in U.S. Pat. No. 3,301,542, disclose a system for treating acidic etching solutions. Swanson et al., in U.S. Pat. No. 3,428,449, disclose extraction of copper from acidic liquors with a phenolic oxime. Spinney, in U.S. Pat. No. 3,440,036, discloses the recovery of copper from copper-bearing solutions. Stephens, in U.S. Pat. No. 3,912,801, discloses the solvent extraction of metals with a cyclic alklylene carbonate. Koehler et al., in U.S. Pat. No. 3,914,374, disclose the removal of residual copper from nickel solutions. Asano et al., in U.S. Pat. No. 3,923,741, disclose an acrylamide aqueous solution refining process. Asano et al., in U.S. Pat. No. 3,941,837, further disclose a method of treating an aqueous solution of acrylamide. Leach et al., in U.S. Pat. No. 4,010,099, disclose settlers for copper liquid extraction systems. Etzel et al., in U.S. Pat. No. 4,210,530, disclose the treatment of metal plating wastes with an unexpanded vermiculite cation exchange column. Dalton, in U.S. Pat. No. 4,231,888, discloses a composition used for extracting copper from aqueous copper salts. Merchant et al., in U.S. Pat. No. 4,239,210, disclose a method of regenerating etchant and recovering etched metal. Brown et al., in U.S. Pat. No. 4,666,683, disclose a process for removal of copper from solutions of chelating agent and copper. Gefvart, in U.S. Pat. No. 5,256,187, discloses the separation of precious metals by an ion exchange process. Guess, in U.S. Pat. No. 5,298,168, discloses a ferrous dithionite process and composition for removing dissolved heavy metals from water. Siefert et al., in U.S. Pat. No. 5,346,627, disclose a method for removing metals from a fluid stream. Marquis et al., in U.S. Pat. No. 5,348,712, disclose the use of carbonates in metal ion extraction. Hayden, in U.S. Pat. No. 5,464,605, discloses a process for the decomposition and removal of peroxides. Abe et al., in U.S. Pat. No. 5,476,883, disclose a preparation process of acrylamide from purified acrylonitrile. Misra et al., in U.S. Pat. No. 5,599,515, disclose a method of removing mercury from solution. Sassaman et al., in U.S. Pat. No. 6,315,906, disclose removing metal ions from wastewater. Filson et al., in U.S. Pat. No. 6,346,195, disclose the ion exchange removal of metals from wastewater. Kemp et al., in U.S. Pat. No. 6,818,129, similarly disclose the ion exchange removal of metal ions from wastewater. However, Kemp et al., in U.S. Pat. No. 6,818,129, notes that if hydrogen peroxide is present, it cannot be present with some resins because of its incompatibility. Kemp et al. further note that ion exchange can be used to attach copper ions, but would not likely work on a polishing slurry stream because of the presence and amount of solids present therein, typically in the form of silica, alumina slurry.